Spread

A spread is the difference between two prices or rates for the same asset, currency, or transaction. It is commonly used to describe the gap between the price at which someone can buy an asset and the price at which they can sell it, or the difference between a reference exchange rate and the rate quoted by a provider.

For users, the spread is often an indirect cost. Even where a product advertises low or zero commission, the provider’s price may include a margin relative to the market price or mid-market exchange rate.

Common meanings of “spread”

The meaning of spread depends on where it appears in the product.

Bid-ask spread

In trading, the bid-ask spread is the difference between:

• Bid price — the highest price a buyer is currently willing to pay for an asset.
• Ask price — the lowest price a seller is currently willing to accept for that asset.

The formula is:

For example, if the bid price for BTC is 60,000 and the ask price is 60,050, the spread is 50. A user buying immediately pays the ask price; a user selling immediately receives the bid price.

The bid-ask spread represents part of the practical cost of entering and exiting a trade. If you buy at the ask price and immediately sell at the bid price, you will generally receive less than you paid, even before any separate trading fees are included.

Exchange-rate spread

In foreign exchange, an exchange-rate spread is the difference between a reference rate — often called the mid-market rate — and the exchange rate quoted to the user by a bank, card issuer, exchange provider, or payment platform.

For example, suppose the market reference rate is:

A provider may offer a customer:

The difference between these rates is the provider’s exchange-rate spread. This difference may function as a pricing margin, even if the provider does not show a separate conversion fee.

Crypto conversion spread

In crypto apps, wallets, and card products, spread may refer to the difference between the displayed market price of a crypto asset and the price offered when the user buys, sells, swaps, or converts that asset.

For example, an app may show Bitcoin’s market price as 60,000, but quote a slightly higher effective price when the user buys Bitcoin and a slightly lower effective price when the user sells it. The difference may reflect liquidity, market volatility, execution risk, pricing methodology, and the provider’s margin.

How spreads work

A spread is usually built into the quoted price rather than shown as a separate line-item fee.

A provider may set separate prices for buying and selling:

• When you buy, the provider quotes a higher price.
• When you sell, the provider quotes a lower price.
• The difference between those prices is the spread.

This model is common in markets where providers source liquidity, manage inventory, absorb short-term price movements, or guarantee a fixed quote for a limited time.

In a crypto conversion flow, the user may see one rate for converting USDC to BTC and a different rate for converting the same BTC back to USDC. The difference is not necessarily an error; it can reflect the buy/sell spread, changes in market prices, and any applicable fees.

Why spreads change

Spreads are not always fixed. They can widen or narrow depending on market conditions and product design.

Market liquidity

Highly liquid assets typically have more buyers and sellers available at nearby prices. This often produces narrower spreads.

Less liquid assets may have fewer available counterparties or a smaller trading volume. In that case, providers may use wider spreads to account for the risk and cost of sourcing or unwinding the transaction.

Market volatility

During fast price movements, providers may widen spreads because the market price can change between the time a quote is generated and the time the transaction is executed.

This is particularly relevant for crypto assets, where prices can move quickly and liquidity can vary substantially across assets and exchanges.

Transaction size

Large transactions can have a wider effective spread than small transactions. A large order may consume available liquidity at the best price and require execution at less favourable prices.

Time of day and market conditions

Spreads may vary during periods of lower trading activity, market stress, major announcements, network congestion, or unusual volatility.

Provider pricing model

Each provider may calculate its quoted rates differently. Some charge an explicit commission and show a narrow spread. Others may advertise zero commission but include more of their revenue in the exchange-rate or conversion spread.

Users should consider the final quoted amount they will receive, not just whether a separate fee is displayed.

Spread vs fee

A spread and a fee both affect the final cost of a transaction, but they are structured differently.

A product can apply both a spread and a separate fee to the same transaction. For example, a crypto platform may quote a rate that includes a conversion spread and also charge a network fee or transaction fee.

For transparency, a good transaction screen should show:

• The amount the user pays.
• The amount the user receives.
• The quoted exchange or conversion rate.
• Any separate fees.
• The quote’s validity period, where relevant.

Spread in crypto trading

In crypto trading, the bid-ask spread is an important indicator of market liquidity and trading cost.

A narrow spread generally suggests that buyers and sellers are placing orders close together. This often means the asset can be traded with less immediate price disadvantage.

A wide spread means there is a larger gap between available buying and selling prices. This can make frequent trading more expensive, especially for market orders that execute immediately at the best available price.

For example:

If a user buys at 100.00 and sells immediately at 99.50, the transaction starts with a 0.50 difference before any explicit trading fees, network costs, or market movement.

Spread in card payments

For cardholders, “spread” most often arises during foreign-currency purchases and crypto conversions rather than regular domestic card payments.

Foreign-currency card purchases

When a cardholder pays in a currency different from the card’s base currency, the payment must be converted. The provider may use a card-network rate, a bank rate, a reference rate plus a markup, or another disclosed pricing method.

The difference between the market reference rate and the rate applied to the transaction can be described as an exchange-rate spread. It may be separate from a foreign transaction fee, or it may be the main source of the provider’s conversion revenue.

Crypto-backed or crypto-linked cards

For crypto card products, a spread may apply when crypto is converted into fiat to settle a card purchase, repay a balance, top up an account, or release collateral.

The exact pricing depends on the product. It may reflect:

• The asset’s current market price.
• Available liquidity.
• The size of the conversion.
• The provider’s quote methodology.
• Market volatility at the time of execution.
• Any separate conversion, trading, or network fees.

Product documentation should clearly explain whether conversion pricing includes a spread and whether additional fees apply.

How users can evaluate a spread

Users do not need to calculate every spread manually, but they should review the final quote before confirming a transaction.

Useful checks include:

• Compare the provider’s quoted rate with a publicly available market reference rate.
• Review how much crypto, fiat, or foreign currency you will receive after conversion.
• Check whether the product lists separate fees in addition to the quoted rate.
• Be cautious with large conversions in volatile or low-liquidity assets.
• Review the quote again if it expires or the market moves substantially.
• Use limit orders, where available, if price certainty matters more than immediate execution.

A small spread may be less important for occasional low-value transactions, but it can become material for frequent trading, larger conversions, or repeated cross-border card spending.